/*============================================================================*/
/*
  VFLib: https://github.com/vinniefalco/VFLib

  Copyright (C) 2008 by Vinnie Falco <vinnie.falco@gmail.com>

  This library contains portions of other open source products covered by
  separate licenses. Please see the corresponding source files for specific
  terms.
  
  VFLib is provided under the terms of The MIT License (MIT):

  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:

  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.

  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  IN THE SOFTWARE.
*/
/*============================================================================*/

#ifndef VF_SEEKINGSAMPLESOURCE_VFHEADER
#define VF_SEEKINGSAMPLESOURCE_VFHEADER

//==============================================================================
/**
  Abstract positionable source of audio samples.

  This interface adds positionable capabilities to a SampleSource. It is
  intended as a facade for @ref PositionableAudioSource, with these features:

  - No thread safety; the caller is responsible for all synchronization.

  - Forward and reverse playback is supported.

  - The looping and total length features have been removed.

  @ingroup vf_audio
*/
class SeekingSampleSource : public SampleSource
{
public:
  enum Direction
  {
    forward,
    reverse
  };

  /** Get the direction for the retrieval of samples.

      @return The direction of playback.
  */
  virtual Direction getNextReadDirection () const = 0;

  /** Set the direction for the retrieval of samples.

      @param direction The direction of playback.
  */

  virtual void setNextReadDirection (Direction direction) = 0;

  /** Get the position of the next returned sample.

      @see setNextReadPosition

      @return The index of the sample which will be read next.
  */
  virtual int64 getNextReadPosition () const = 0;

  /** Move the read position.

      Calling this indicates that the next call to
      SampleSource::getNextAudioBlock() should return samples from this
      position.

      @param newPosition The index of the sample to read next.
  */
  virtual void setNextReadPosition (int64 newPosition) = 0;

public:
  //============================================================================
  /**
    Presents a SeekingSampleSource as a PositionableAudioSourceAdapter.

    @ingroup vf_audio
  */
  class PositionableAudioSourceAdapter : public PositionableAudioSource
                                       , Uncopyable
  {
  public:
    PositionableAudioSourceAdapter (SeekingSampleSource* source,
                                    bool takeOwnership);

    void setNextReadPosition (int64 newPosition);

    int64 getNextReadPosition() const;

    int64 getTotalLength() const;

    bool isLooping() const;

    void setLooping (bool shouldLoop);

    void prepareToPlay (int samplesPerBlockExpected,
                        double sampleRate);

    void releaseResources();

    void getNextAudioBlock (const AudioSourceChannelInfo& bufferToFill);

  private:
    OptionalScopedPointer <SeekingSampleSource> m_source;
  };
};

#endif
